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1.
Front Cardiovasc Med ; 11: 1297218, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694566

RESUMO

Introduction: To investigate the prognostic value of the consistency between the residual quantitative flow ratio (QFR) and postpercutaneous coronary intervention (PCI) QFR in patients undergoing revascularization. Methods: This was a single-center, retrospective, observational study. All enrolled patients were divided into five groups according to the ΔQFR (defined as the value of the post-PCI QFR minus the residual QFR): (1) Overanticipated group; (2) Slightly overanticipated group; (3) Consistent group; (4) Slightly underanticipated group; and (5) Underanticipated group. The primary outcome was the 5-year target vessel failure (TVF). Results: A total of 1373 patients were included in the final analysis. The pre-PCI QFR and post-PCI QFR were significantly different among the five groups. TVF within 5 years occurred in 189 patients in all the groups. The incidence of TVF was significantly greater in the underanticipated group than in the consistent group (P = 0.008), whereas no significant differences were found when comparing the underanticipated group with the other three groups. Restricted cubic spline regression analysis showed that the risk of TVF was nonlinearly related to the ΔQFR. A multivariate Cox regression model revealed that a ΔQFR≤ -0.1 was an independent risk factor for TVF. Conclusions: The consistency between the residual QFR and post-PCI QFR may be associated with the long-term prognosis of patients. Patients whose post-PCI QFR is significantly lower than the residual QFR may be at greater risk of TVF. An aggressive PCI strategy for lesions is anticipated to have less functional benefit and may not result in a better clinical outcome.

2.
Materials (Basel) ; 17(8)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38673274

RESUMO

Fluorescent carbon dots (CDs) are a new type of photoluminescent nanomaterial. Solid-state CDs usually undergo fluorescence quenching due to direct π-π* interactions and superabundant energy resonance transfer. Therefore, the preparation of solid-state fluorescent CDs is a challenge, especially the preparation of long wavelength solid-state CDs. In this research, long wavelength emission CDs were successfully synthesized by solvothermal methods, and the prepared CDs showed good hydrophobicity. The composite solid-state CDs/PVP (Polyvinyl pyrrolidone) can emit strong red fluorescence, and the quantum yield (QY) of the CDs/PVP powder reaches 18.9%. The prepared CDs/PVP solid-state powder was successfully applied to latent fingerprint detection. The results indicate that the latent fingerprints developed by CDs/PVP powder have a fine definition and high contrast visualization effect, which proves that the prepared CDs/PVP has great application potential in latent fingerprint detection. This study may provide inspiration and ideas for the design of new hydrophobic CDs.

3.
Materials (Basel) ; 17(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38612204

RESUMO

In this paper, La2Ce2O7 powders co-activated by Ho3+ and Yb3+ were synthesized by a high temperature solid-state reaction. Both Ho3+ and Yb3+ substitute the La3+ sites in the La2Ce2O7 lattice, where the Ho3+ concentration is 0.5 at.% and the Yb3+ concentration varies in the range of 10~18% at.%. Pumped by a 980 nm laser, the up-conversion (UC) green emission peak at 547 nm and the red emission at 661 nm were detected. When the doping concentration of Ho3+ and Yb3+ are 0.5 at.% and 14% at.%, respectively, the UC emission reaches the strongest intensity. The temperature-sensing performance of La2Ce2O7:Ho3+ with Yb3+ was studied in the temperature range of 303-483 K, where the highest relative sensitivity (Sr) is 0.0129 K-1 at 483 K. The results show that the powder La2Ce2O7:Ho3+, Yb3+ can be a potential candidate for remote temperature sensors.

4.
Diabetes Res Clin Pract ; 206: 111013, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37972858

RESUMO

AIMS: We aimed to investigate the impact of percutaneous coronary intervention (PCI) and diabetes mellitus (DM) on short- and long-term prognosis in patients with coronary artery disease using three-vessel quantitative flow ratio (3 V-QFR) assessment. METHODS: A retrospective analysis of 2440 vessels in 1181 patients who underwent PCI was performed. The patients were categorized according to the presence or absence of DM and the median 3 V-QFR. The primary outcome was the occurrence of major adverse cardiac events (MACE), defined as a combination of cardiovascular death, myocardial infarction, and ischemia-driven revascularization, over a 5-year period. RESULTS: The pre-PCI and post-PCI 3 V-QFR values for the entire population were 2.37 (2.04-2.56) and 2.94 (2.82-3.00), respectively. Landmark analysis showed that the incidence of MACE was comparable among all groups within the first year (log-rank p = 0.088). Over the course of 2 years, the incidence of MACE was higher in both groups with a post-PCI 3 V-QFR < 2.94 (log-rank p < 0.001). However, from 2 to 5 years, patients with DM had higher rates of MACE (log-rank p = 0.013). CONCLUSIONS: In the short term, a low post-PCI 3 V-QFR is a predictor of high risk for MACE. However, in the long term, DM emerges as the dominant risk factor.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/etiologia , Diabetes Mellitus/etiologia , Prognóstico , Fatores de Risco , Angiografia Coronária
5.
Materials (Basel) ; 16(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37687700

RESUMO

Lu3Al5O12:Ce3+ phosphor ceramics were fabricated by vacuum sintering. On this basis, a bi-layer composite phosphor was prepared by low-temperature sintering to cover the phosphor ceramics with a layer of SrAlSiN3:Eu2+-phosphor-in-glass (PiG). The optical, thermal, and colorimetric properties of LuAG:Ce3+ phosphor ceramics, SrAlSiN3:Eu2+ phosphors and SrAlSiN3:Eu2+-PiG were studied individually. Combining the bi-layer composite phosphors with the blue LED chip, it is found that the spectrum can be adjusted by varying the doping concentration of SrAlSiN3:Eu2+-PiG and the thickness of Lu3Al5O12:Ce3+ phosphor ceramics. The maximal color rendering index value of the white LED is 86, and the R9 is 61. Under the excitation of a laser diode, the maximum phosphor conversion efficacy of the bi-layer composite phosphors is 120 lm/W, the Ra is 83, and the correlated color temperature is 4534 K. These results show that the bi-layer composite phosphor ceramic is a candidate material to achieve high color rendering index for high brightness lighting.

6.
Nanomaterials (Basel) ; 13(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37242047

RESUMO

The nonlinear optical (NLO) response of indium tin oxide films covered with Au@Ag colloid layer was characterized by a femtosecond single-beam open aperture (OA) Z-scan technique in this study. As the Au@Ag thickness increased, the transition from saturated absorption (SA) to reverse saturated absorption (RSA) was found in these ITO matrix composites. The nonlinear absorption coefficient for these composite materials can be regulated from -6.85 × 10-7 m/W to 26.06 × 10-7 m/W. In addition, this work also characterized the structure, morphology, and other optical properties of the specimen, and the finite-difference time-domain (FDTD) results were consistent with the experimental results. The NLO response of the ITO/Au@Ag composites can be attributed to the phase properties, synergistic competition effect, strong interaction based on the epsilon-near-zero (ENZ) mode, and localized surface plasmon resonance (LSPR) between the indium tin oxide films and Au@Ag.

7.
Materials (Basel) ; 16(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37176253

RESUMO

Cerium-doped gadolinium aluminum gallium garnet (Ce3+:Gd3Al3Ga2O12, Ce3+:GAGG) ceramic is a promising scintillation material. In this study, Ce3+:Gd3Al3Ga2O12 scintillation ceramics were prepared by the one-step sintering of commercially available Gd2O3, Al2O3, Ga2O3, and CeO2 powders in a flowing oxygen atmosphere at 1600 °C by solid-phase reaction sintering. For all the Ce3+:Gd3Al3Ga2O12 ceramic samples doped with different amounts of Ce3+ doping, dense ceramics were obtained. The structure, photoluminescence, and scintillation properties of the Ce3+:Gd3Al3Ga2O12 ceramics have been investigated. The average grain size of samples sintered at 1600 °C is about 2 µm. The X-ray excitation luminescence peak is around 560 nm, which is consistent with that of Ce3+:Gd3Al3Ga2O12 single crystals, matching well with the computed tomography X-ray detector's response sensitivity. The light yield is higher compared to the standard reference sample-lutetium yttrium orthosilicate single crystal.

8.
Opt Express ; 31(7): 11940-11953, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155817

RESUMO

This study proposed the synergistic merging of twisted-nematic liquid crystals (LCs) and nanograting embedded etalon structures for plasmonic structure color generation, realizing dynamic multifunctional metadevices. Metallic nanogratings and dielectric cavities were designed to provide color selectivity at visible wavelengths. Meanwhile, the polarization for the transmission of light could be actively manipulated by electrically modulating these integrated LCs. Moreover, manufacturing independent metadevices as single storage units with electrically controlled programmability and addressability facilitated secure information encoding and secretive transfer by dynamic high-contrast images. The approaches will pave the way for the development of customized optical storage devices and information encryption.

9.
Opt Express ; 31(2): 3083-3091, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785307

RESUMO

Although structural colors based on nanostructures have attracted many researchers' attentions due to their superior durability and high resolution, most previous reports focused on the static and dynamic structural colors in reflection mode and few researchers focus on the static and dynamic transmission colors for high-saturation RGB models. Here, the hybrid Al-Si3N4 nanogratings with the top SiO2 capping layer and the bottom MgF2 layer that can switch full-hue and high-saturation transmitted structural colors on and off completely by changing the polarization state are theoretically demonstrated. Meanwhile, the hybrid Al-Si3N4 nanogratings with the top capping layer and the bottom layer also achieve the transmittance spectra with the full width at half maximum of ∼58 nm and the transmittance efficiency of over 70% in the on state. The added top capping layer and bottom layer can suppress the sideband of transmittance spectra in the on state and maintain the near-zero transmittance in the off state, thus improving the switching performance between bright and dark states. The realizable high-saturation colors in the on state can take up 125% sRGB space and 80% Adobe sRGB space. More interestingly, with the incident angle varying from 0° to 50°, full-hue color can be also realized in the on state and nearly black color can be also maintained in the off state. The strategy will provide potential applications in advanced color encryption and multichannel imaging.

10.
Opt Express ; 31(1): 95-106, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606953

RESUMO

MgAl2O4:Mn2+ transparent ceramics were fabricated by reactive spark plasma sintering (SPS). The ceramic samples show narrow-band green emission under the 450 nm blue light excitation, which is corresponding to 4T1(4 G)-6A1(6S) transition of Mn2+ in the tetrahedral site. The emission peak of the Mg0.93Al2O4:0.07Mn2+ ceramic sample was located at 525 nm with the full-width at half-maximum (FWHM) value of 36 nm. The internal quantum yield (IQY) of Mg0.93Al2O4:0.07Mn2+ reached 63%. The emission intensity remained ∼98% at 150 °C compared to its initial value at room temperature, showing excellent thermal quenching performance. The results indicated that MgAl2O4:Mn2+ ceramic phosphor is a promising candidate for high brightness, wide gamut display backlight applications.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 268: 120686, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-34890874

RESUMO

A series of WO3-x thin films with defects were obtained by thermal treatments from laser irradiation and annealing, respectively. The corresponding tunability of localized surface plasmon resonance properties and the enhancement of Raman scattering intensity were realized due to the defects in the WO3-x thin films after thermal treatments. With the changes of either laser power or annealing temperature, the crystalline quality of WO3-x thin film was declined with a red shift of the surface plasmon resonance wavelength from 464 nm to 482 nm. The as-treated WO3-x film shows good uniformity and reproducibility in Surface-enhanced Raman spectroscopy measurement, the detection limit for dye methylene blue can reach 10-8 mol/L, and enhancement factor is 1.38 × 106. Furthermore, the simulation result of finite-difference time-domain showed a substantial agreement with experimental results.

12.
Dalton Trans ; 51(5): 1784-1790, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34935806

RESUMO

In this paper, BaAl2O4:Eu2+-Al2O3 ceramics were successfully prepared by spark plasma sintering (SPS). The optical properties of the multiphase ceramics doped with different concentrations of alumina were studied. Under excitation with 365 nm ultraviolet light, the luminescent color of the samples can be adjusted by changing the sintering temperature and the contents of alumina addition. The temperature dependent fluorescence spectra in the temperature range of 4 K-434 K were measured, and the temperature dependent fluorescence intensity ratio (FIR) was calculated. The FIR monotonically increased with the increase of temperature, indicating that the material could be used for temperature sensing. The absolute sensitivity Sa of the temperature sensing fluorescent material is larger than 0.005 K-1 at 334 K-434 K, and the relative sensitivity Sr is larger than 0.75% K-1 at 304 K-434 K. The results show that the BaAl2O4:Eu2+-Al2O3 ceramic is a promising non-contact temperature sensing material.

13.
Micromachines (Basel) ; 12(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34832732

RESUMO

In this paper, a tunable absorber composed of asymmetric grating based on a graphene-dielectric-metal structure is proposed. The absorption of the absorber can be modified from 99.99% to 61.73% in the near-infrared by varying the Fermi energy of graphene, and the absorption wavelength can be tuned by varying the grating period. Furthermore, the influence of other geometrical parameters, the incident angle, and polarization are analyzed in detail by a finite-difference time-domain simulation. The graphene absorbers proposed in this paper have potential applications in the fields of stealth, sense, and photoelectric conversion. When the absorber that we propose is used as a gas sensor, the sensitivity of 200 nm/RIU with FOM can reach up to 159 RIU-1.

14.
Opt Express ; 29(8): 12763-12771, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33985026

RESUMO

A variety of techniques have been proposed for fabricating high-density, high-numerical-aperture microlens arrays. However, a microlens array with a uniform focal length has a narrow depth of field, limiting the ability of depth perception. In this paper, we report on a fabrication method of multi-focus microlens arrays. The method for the preparation of the mold of the microlens array is based on 3D printing and microfluidic manipulation techniques. In the preparation of the mold, curved surfaces of the photo-curable resin with different curvatures are formed in the 3D printed microholes whose walls are inclined with different angles. The replicated microlens array consists of hundreds of lenslets with a uniform diameter of 500 µm and different focal lengths ranging from 635 µm to 970 µm. The multi-focus microlens array is capable of extending the depth of field for capturing clear images of objects at different distances ranging from 14.3 mm to 45.5 mm. The multi-focus microlens array has the potential to be used in a diversity of large-depth-of-field imaging and large-range depth perception applications.

15.
Opt Express ; 28(17): 25073-25084, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32907037

RESUMO

High-performance omnidirectional transmissive chromatic polarizers based on a one-dimensional dielectric-metal-dielectric subwavelength grating structure are proposed. The incident angle-insensitive properties, azimuthal angle-insensitive properties and polarization features are investigated thoroughly to realize the proposed omnidirectional transmissive chromatic polarizers. The color difference at different angles for the proposed yellow polarizers is less than 0.9746, and the extinction ratio at different angles for the proposed cyan polarizers exceeds 26. Analysis of the power density profiles for the transverse electric (TE) and transverse magnetic (TM) polarizations show that surface plasmon resonance and high refractive index contrast properties lead to excellent polarization features and high angular tolerance.

16.
Nanotechnology ; 31(14): 145715, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31860904

RESUMO

Photocatalytic water splitting with solar energy is the most promising and environmentally friendly hydrogen production method. Having an efficient and cost-effective photocatalyst is key to hydrogen production. Cu dopant has been shown to greatly enhance photocatalytic activities. In this work, Cu2+ ions were doped into Beta zeolite powders (Cu-Beta) by the ion exchange method. The hydrogen evolution efficiency of Cu-Beta was much higher than the raw Beta zeolites without Cu loading. After solid phase reaction, the band gap of Cu-Beta reduced from 3.48 eV to less than 2 eV, and as a result enhanced the optical absorption intensity, particularly in the visible region. The best hydrogen evolution efficiency was 102.12 µmol · g-1 · h-1 when the treated temperature was 900 °C (Cu-Beta-900). The temperature of the solid phase reaction had an important influence on the photocatalytic performance of Cu-Beta; a suitable reaction temperature can greatly improve its photocatalytic performance.

17.
Opt Express ; 27(22): 32666-32678, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684475

RESUMO

An Al2O3:Mn4+, Mg2+ red emitting ceramic phosphor, which can be effectively excited by ultraviolet and blue light, was successfully synthesized via solid-state reaction in an oxygen and air atmosphere. The ceramic sintered in oxygen atmosphere has higher optical transmittance and stronger luminescence intensity than the ceramic sintered in the air, which is more suitable for LED application. Since the structure of α-Al2O3 is very simple, it is convenient to study the factors affecting the Mn4+ luminescence. The crystal-strength parameter Dq, Racah parameters B and C, and the nephelauxetic ratio ß1 were calculated to investigate the influence of crystal field strength and nephelauxetic effect on the emission of Mn4+ in the Al2O3 host. The ratio of Dq to B was 1.74, which was lower than 2.2. This indicated that the Mn4+ ions in the α-Al2O3 host were in a weak crystal field environment. Under the 395 nm and 460 nm excitations, quantum yields (QY) of the sample were measured to be 46% and 28.7%, respectively. The density measured by the Archimedes method was 3.61 g/cm3. The ceramic also showed an excellent thermal conductivity value, which was as high as 26.27 W·m-1·K-1@30 °C.

18.
Nanomaterials (Basel) ; 9(6)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167393

RESUMO

Sub-wavelength artificial photonic structures can be introduced to tailor and modulate the spectrum of materials, thus expanding the optical applications of these materials. On the basis of SiO2/Cu/ITO arrays, a hybrid coupled resonance (HCR) mechanism, including the epsilon-near-zero (ENZ) mode of ITO, local surface plasmon resonance (LSPR) mode and the microstructural gap resonance (GR) mode, was proposed and researched by systematically regulating the array period and layer thickness. The optical absorptions of the arrays were simulated under different conditions by the finite-difference time-domain (FDTD) method. ITO films were prepared and characterized to verify the existence of ENZ mode and Mie theory was used to describe the LSPR mode. The cross-sectional electric field distribution was analyzed while SiO2/Cu/ITO multilayers were also fabricated, of which absorption was measured and calculated by Macleod simulation to prove the existence of GR and LSPR mode. Finally, the broad-band tailoring of optical absorption peaks from 673 nm to 1873 nm with the intensities from 1.8 to 0.41 was realized, which expands the applications of ITO-based plasmonic metamaterials in the near infrared (NIR) region.

19.
Nanomaterials (Basel) ; 8(11)2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405091

RESUMO

Defect-induced tunable permittivity of Epsilon-Near-Zero (ENZ) in indium tin oxide (ITO) thin films via annealing at different temperatures with mixed gases (98% Ar, 2% O2) was reported. Red-shift of λENZ (Epsilon-Near-Zero wavelength) from 1422 nm to 1995 nm in wavelength was observed. The modulation of permittivity is dominated by the transformation of plasma oscillation frequency and carrier concentration depending on Drude model, which was produced by the formation of structural defects and the reduction of oxygen vacancy defects during annealing. The evolution of defects can be inferred by means of X-ray diffraction (XRD), atomic force microscopy (AFM), and Raman spectroscopy. The optical bandgaps (Eg) were investigated to explain the existence of defect states. And the formation of structure defects and the electric field enhancement were further verified by finite-difference time domain (FDTD) simulation.

20.
Nanotechnology ; 29(1): 015705, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29139394

RESUMO

Tuning the localized surface plasmon resonance (LSPR) in doped semiconductor nanoparticles (NPs), which represents an important characteristic in LSPR sensor applications, still remains a challenge. Here, indium tin oxide/indium tin alloy (ITO/In-Sn) bilayer films were deposited by electron beam evaporation and the properties, such as the LSPR and surface morphology, were investigated by UV-VIS-NIR double beam spectrophotometer and atomic force microscopy (AFM), respectively. By simply engineering the thickness of ITO/In-Sn NPs without any microstructure fabrications, the LSPR wavelength of ITO NPs can be tuned by a large amount from 858 to 1758 nm. AFM images show that the strong LSPR of ITO NPs is closely related to the enhanced coupling between ITO and In-Sn NPs. Blue shifts of ITO LSPR from 1256 to 1104 nm are also observed in the as-annealed samples due to the higher free carrier concentration. Meanwhile, we also demonstrated that the ITO LSPR in ITO/In-Sn NPs structures has good sensitivity to the surrounding media and stability after 30 d exposure in air, enabling its application prospects in many biosensing devices.

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